Remove duplicated function name that confuses the TS compiler.

With this small change we have much more sane inferred types
when Unexpected is required() within, for example, VSCode.

lib/createTopLevelExpect.js

@@ -1462,7 +1462,7 @@ expectPrototype._executeExpect = function(
   return oathbreaker(assertionRule.handler(wrappedExpect, subject, ...args));
 };
 
-expectPrototype._expect = function expect(context, args, forwardedFlags) {
+expectPrototype._expect = function(context, args, forwardedFlags) {
   const subject = args[0];
   const testDescriptionString = args[1];